Question

Find the measures of the unknown angles in the following:
​

Answer 1

Answer:

a) 42+58+r=180

100+r=180

r=180-100=80

b) 40+ 115+o= 180

155+o = 180

o= 180-155

0= 25

Answer 2

Answer:

(a) 80° (b) 25°

Step-by-step explanation:

(a)

Let unknown angle R = x

angle Q = 42°

angle P = 58°

angle R + angle Q + angle P = 180° [ because of angle sum property of triangle ]

therefore,

x + 42° + 58° = 180°

x + 100° = 180°

taking 100° to right side it will become negative & we will get

x = 180° - 100° = 80°

x = 80°

(b)

Let unkown angle O = x

Given

angle N = 115°

angle M =40°

angle O + angle N + angle M = 180° [ because of angle sum property of triangle]

therefore,

x + 40° + 115° = 180°

x + 155° = 180°

taking 155° to right side it will become -155°

x = 180° - 155°

x = 25°